1. Field of the Invention
This invention relates to an organic waste processor and processing method, and in particular to an organic waste processor and processing method in which organic waste is processed using a processing material upon which microorganisms are supported.
2. Description of the Related Art
In general, organic waste discharged from homes is collected separately as raw garbage or burnable garbage by local public bodies, burnt, and then buried. In this waste disposal system, however, a problem is now arising in that a large amount of manpower is required to collect the waste and a large area is required to bury it.
To resolve this problem, an organic waste processor suitable for the home which uses microorganisms to convert organic waste to compost is commercially available. The compost-like product of this organic waste processor may for example be re-used as fertilizer for home vegetable gardens.
However this processor merely converts organic waste into a compost-like product, and does not destroy the waste. It was therefore unsuitable for homes which did not have the capacity to re-use the product.
In recent years, devices have been proposed wherein, after converting the organic waste to a compost-like product, it was further decomposed into low molecular weight products such as water or carbon dioxide gas, e.g. as disclosed in Japanese Utility Model Laid-Open Publication Hei 5-88683 (Koho). According to this method, microorganisms having decomposing ability were supported on special wood chips as a processing material, the water content of this material was maintained at approximately 63%, and organic waste was then mixed with it and stirred. Due to the stirring, the microorganisms were aerobically cultivated, and the organic waste was accordingly digested and decomposed into low molecular weight products such as water and carbon dioxide. Consequently, in a device functioning according to this method, the organic waste is effectively completely destroyed, and it may therefore conveniently be used even when there is no ability to dispose of compost.
However as described above, in a device which decomposes and digests organic waste while maintaining the water content of the processing material at 65%, after a long period of use such as for example 3 months, the processing material in the device sticks together to form lumps. It appears that when decomposition products adhere to the processing material and a certain amount of water is added, these products become viscous and cause the material to lump together.
When the processing material sticks together and forms lumps, the microorganisms contained in the material are unable to grow aerobically. At the same time, their contact with the organic waste is prevented so that their ability to digest and decompose the waste declines. Also, although the microorganisms supported on the processing material cannot grow aerobically, they do grow under anaerobic conditions. When microorganisms grow under anaerobic conditions in this way, a characteristic foul odor is produced. Hence using conventional processing materials, it was necessary to regularly replace the material.
This invention, which was conceived in view of the above problems, therefore aims to suppress the water content of the processing material so as to suppress the formation or development of lumps due to sticking together of processing material, thereby providing an organic waste processor in which the processing material can be used for a long time period.
It is a further object of this invention to provide an organic waste processor wherein, as a result of adjusting the water content of the processing material by controlling air circulation, the pH or salt concentration in the processing tank can be maintained at such a level as to suppress the proliferation of bacteria that cause food poisoning.